While differences in the health of individuals can be attributed to a multiplicity of causes – heredity, environmental factors, health behaviors, access to medical care and others - socio- economic factors such as income, educational attainment and racism are recognized as powerful “social determinants” of population health. Disequities in income and education, for example, have been found to drive inequalities in access to health care and disparities in health status among population sub-groups. Disparities in health outcomes related to social determinants have been well documented at the national and state levels but are less well documented at the local level. Where this information is available, data on health disparities related to social determinants in Sonoma County are highlighted throughout the Profile, particularly related to risk behaviors, access to health care services and self-reported health status.
The two graphs which follow use census data on neighborhood poverty groups to highlight the relationship between mortality, chronic disease and income. In neighborhoods where more than 15% of residents are living at or below Federal Poverty Level (FPL), the death rate from chronic disease is substantially higher (528.5/100,000) than in neighborhoods where fewer than 5% of residents are living below FPL (428.9/100,000). Similarly, all-cause mortality rates are higher in neighborhoods with high concentrations of low-income residents.
Death rates from leading causes of chronic disease* by neighborhood poverty, Sonoma County 2005-2009
*Cancer, coronary heart disease, stroke, chronic lower respiratory disease, and diabetes
All cause mortality by neighborhood poverty, Sonoma County 2005-2009
Source:California Department of Public Health, Death StatisticalMaster Files (2005-2009)
Information gathered through the St. Joseph Health System Behavioral Risk Factor Survey, conducted in Sonoma County in June 2012, further illustrates the links between social determinants, predominantly income and educational attainment, and disparities in health and health care access.
Source:St. Joseph Health, Behavioral Risk Factor Surveillance System
Self-reported physical health status varies significantly by income and education. For example:
- Among respondents, 62.8% of individuals with incomes over 200% of FPL rated their health as “very good” or “excellent” as compared with 23.1% of those living below FPL.
- Respondents with the highest education levels (college graduate or above) reported very good/excellent health nearly three times more often than did those without a high school diploma (66.4%/22.2%).
- And, 29% of survey respondents with incomes below FPL reported that their health was “not good” on 10 or more days of the past 30 days as compared with 9% of those living above 200% FPL.
The survey demonstrated similar links with regard to mental health status.
- Among respondents living under 200% of FPL, 40.2% reported “excellent” or “very good” mental health as compared with 71.2% of those with higher incomes.
- Among those living below FPL, over 30% report only “fair” or “poor” mental health.
- Among Sonoma County adults with the highest education levels (college graduate or above), 72% report excellent/very good mental health as compared with 28.6% of those without high school degree. Over 30% of these respondents report fair/poor mental health.
Social determinants can also drive differences in access to health care and services.
- More respondents with incomes below FPL reported difficulty finding medical care “when they needed it” than did those living at 200% FPL and above (5.3%/23%).
- Among adults with incomes between 100-200% of FPL, over 15% reported similar difficulty.
- Over 25% of those with incomes below 200% FPL reported that they did not get “a prescription medicine that they needed” during the past year because they could not afford it while 5.8% of those reporting higher incomes did.
The survey revealed similar disparities with regard to dental care access.
- 77% of survey respondents with incomes at 200% of FPL or higher reported having had their teeth cleaned by a dentist or dental hygienist within the past year, as compared with 47% of those with incomes below that level.
- Among respondents living below FPL, only 35% report cleaning within the past year; 16% report not having had their teeth cleaned in the past 5 years; and 11% report never having had them cleaned.
Ethnicity, per se, is not a social determinant of health. However, because Hispanics and other populations of color in Sonoma County are more likely, on average, to be lower-income and less well educated than White, non-Hispanics, they are often disproportionately impacted by social determinants and more likely suffer health disparities because of this. For example:
- While 58.7% of non-Hispanic whites rated their health as “very good” or “excellent,” only 35.9% of Hispanics did so.
- Hispanic survey respondents also reported higher rates of fair/poor mental health (18.9%) than did white non-Hispanics (11.7%).
- Among Hispanic survey respondents, 12.4% reported difficulty finding a doctor as compared with 7.1% of non-Hispanic Whites.
- 19% of Hispanic respondents said they did not have a usual source of care, as compared with 8.9% of non-Hispanic Whites.
- Just fewer than 50% of Hispanic respondents reported that they had no health insurance coverage, as compared with 12% of non-Hispanic Whites.
More data on which groups are most affected by social determinants and how these determinants are impacting health outcomes over time are needed to create a clear picture of population health status in Sonoma County and to develop strategies to address resulting health disparities.